Science & Mathematics - 1 October 2007

2007-10-01 17:27:31 · 7 answers · asked by ruas slickyboy 2 in Mathematics

2007-10-01 17:23:40 · 5 answers · asked by jose8153@sbcglobal.net 1 in Mathematics

2007-10-01 17:21:49 · 2 answers · asked by Anonymous in Mathematics

You push a 34.4 kg crate at a constant speed of 1.66 m/s across a horizontal floor with coefficient of kinetic friction 0.34. The acceleration of gravity is 9.8 m/s^2.
a) At what rate is work being done on the crate by you? Answer in W.
b) At what rate is energy being dissipated by the frictional force? Answer in W.

2007-10-01 17:19:44 · 1 answers · asked by Ron108 1 in Physics

I mean it could of been to close to the sun in which we would burn up, But if it was too cold, we would freeze to death. We just happen to be in the right spot, Therefore there must be a higher power controlling the universe. I mean what are the odds?

2007-10-01 17:18:55 · 11 answers · asked by James the Just 3 in Astronomy & Space

varies from 0 N to 33.4 N as we stretch the spring by moving one end 7.06 cm from its unstressed position.
a) Find the force constant of the spring. Answer in N/m
b) Find the work done in stretching the spring. Answer in J.

2007-10-01 17:16:53 · 2 answers · asked by Ron108 1 in Physics

2007-10-01 17:15:29 · 3 answers · asked by sweets 1 in Physics

I have a degree in Chemistry and currently I am doing graduate courses in Statistics. There are many interesting fields to pursue with Chemistry and Statistics. But I want to solicit from you guys any suggestion on what would be the most rewarding field of endeavor I could pursue. I would appreciate answers from the more senior and more experienced answerers. (add info: I enjoy data interpretation more than the actual laboratory work)

2007-10-01 17:12:39 · 4 answers · asked by fossegrim 2 in Other - Science

I am almost finished with my math homework, but I am stuck on a few final word problems. Those who may help do not have to give me the answers if they do not wish to, but a push in the right direction would really help me! Please show me your work. Thank you so much to anyone who answers!

A freight train travels 90 miles in the same time that a passenger train travels 150 miles. If the passenger train goes 30 miles per hour faster than the freight train, find the rate of each. (I know RxT=D, but this one is stumping me...)

Sally walks to her friend's house at the rate of 3 miles per hour and then runs home at the rate of 6 miles per hour. How far does Sally live from her friend if the round trip takes 30 minutes?

How many liters of pure alcohol must be added to 20 liters of a 30% solution to obtain a 35% solution? (Is the answer 1.2 liters?)

If $10,000 is invested part at 7% and part at 9%, and if the total annual return is $840, how much was invested at 7%?

2007-10-01 17:11:33 · 5 answers · asked by mrsdynamite 2 in Mathematics

My friend and I were talking one day, we where coming up with theories how God communicated with humans. One of the things I said if thought is a form of energy the one person can send thoughts to another. I was wondering if thought if a form of energy NOT that it uses energy.

2007-10-01 17:09:26 · 5 answers · asked by acdc 2 in Physics

2007-10-01 16:59:49 · 2 answers · asked by SICK MY DUCK! 1 in Chemistry

How would i go about designing the plasma membrane of a "hypothetical" plasma membrane of a mineral-absorbing
cell, with reference to mineral-permeable channel proteins and mineral-transporting active-transport proteins


I need help BADLY!

2007-10-01 16:59:30 · 3 answers · asked by isaiah`s mommy 2 in Biology

We were asked to graph results from an experiment dealing with a projectile, and we were asked to make the X axis velocity and the Y axis distance. There are then questions about slope and time. As far as I can tell, T=v/x from the original equation, x/t=v. I find nothing about the equation flipped. I am also sure that the last time I checked, slope is rise (Y) over run (X). Is there a good reason for this madness or is he the nutty professor?

2007-10-01 16:56:08 · 4 answers · asked by scripta_elegans 2 in Physics

A 5 percent glucose solution is frequently administered to the blood of persons who have undergone surgery. Why? What affect does this have to the person or to their blood?

2007-10-01 16:50:21 · 5 answers · asked by Anonymous in Medicine

There is a large circle with radius R. Inside this circle is placed another circle with radius r (< R) so that the two circles are concentric. Now, in the region between the circumferences of the two circles, place N circles (of diameter R-r) such that each small circle has one and only one point of contact with each large circle and with two adjacent small circles.

Basically, imagine that this is like a bearing system.

Is this possible? If so, what is the radius of the smaller of the two large circles (r) in terms of the radius of the largest circle (R). Also, how many "small" circles can fit in the space between the two "large" circles?

I hope this is clear. I thought about this puzzle earlier today and can't figure out how to solve it. I guess that's what 15 years of no formal math can do to a person... *sigh*

2007-10-01 16:47:42 · 9 answers · asked by Anonymous in Mathematics

does anyone know

the relationship between acceleration
and net force?

and the relationship between acceleration and mass?

2007-10-01 16:45:39 · 2 answers · asked by 123456 2 in Physics

A child slides down a slide with a 20° incline, and at the bottom her speed is precisely one-fourth what it would have been if the slide had been frictionless. Calculate the coefficient of kinetic friction between the slide and the child

2007-10-01 16:44:58 · 2 answers · asked by xxzeroennaxx 1 in Physics

"Marissa's car accelerates at an average rate of 2.6 m/s^2. Calculate how long it takes her car to accelerate from 24.6 m/s to 26.8 m/s."

Easy, but for some reason, I can't get it.
I've tried, but it's not working out, haha.

If you could, explain while solving, please.
Thanks!

2007-10-01 16:44:54 · 4 answers · asked by Anonymous in Mathematics

Suppose that a 5-foot-long object falls from a 35-foot height and that you are 6 feet tall and standing directly under the object.
How long do you have to get out of the way?
Time = ? seconds

I'm getting ~2 sec but it seems to be wrong!

2007-10-01 16:43:46 · 1 answers · asked by Carlos 1 in Mathematics

2007-10-01 16:38:49 · 5 answers · asked by SICK MY DUCK! 1 in Chemistry

The temp is always in 70s and it is nice and cool. People do not have heater or ac in their homes. What is the reason for this ?

2007-10-01 16:38:47 · 7 answers · asked by BL 1 in Weather

i have come up with some kind of an idea for a metal shed and i want to mass produce it . so where do i turn for a start?
i was thinking of a custom metal fabrication company but they might not be the right choice for mass production

2007-10-01 16:34:21 · 1 answers · asked by Shie W 1 in Engineering

function: f(x)=8x^4 - 23x^3 + 23x^2 - 26x + 15
Intervals: [-1,0], [0,1], [1,2], [2,3]

For some reason, my instructor didn't cover how to do these in class, but he assigned them for our homework. I have no idea how to go about doing them. Any help is appreciated, thanks!

2007-10-01 16:31:39 · 2 answers · asked by AnonymousOne 2 in Mathematics

Find an approximate value for the rate at which the moon orbits the earth. Assume that the moon’s orbit is circular

2007-10-01 16:30:28 · 2 answers · asked by ? 1 in Astronomy & Space

2007-10-01 16:27:45 · 3 answers · asked by Anonymous in Chemistry

As far as I know it's to do with rainfall over tea plantations, can anyone shed any more light on it

2007-10-01 16:19:14 · 6 answers · asked by Trevor 7 in Weather

A 5 percent glucose solution is frequently administered to the blood of persons who have undergone surgery. Why? What affect does this have to the person or to their blood?

2007-10-01 16:17:21 · 3 answers · asked by Anonymous in Medicine

so it can be used for domestic distributation

2007-10-01 16:15:10 · 4 answers · asked by Dallas B 1 in Engineering

The mass of a cube of iron is 355g. Iron has a density of 7.87 g/cm3. What is the mass of a cube of lead which has the same dimensions?

I don't understand the wording of the problem....And how do I calculate this? Please be clear, don't just show a few numbers

2007-10-01 16:12:50 · 1 answers · asked by Anonymous in Chemistry

Which of the following ions occurs commonly?
N3+
S6+
O2-
Ca+
Cl+

2. Sodium hydroxide, also known as caustic soda, is used to neutralize acids and to treat cellulose in making of cellophane. Calculate the number of moles of solute in 1.875 L of 1.356 M NaOH solution.
2.543 mol
1.383 mol
0.7232 mol
0.3932 mol
0.001383 mol

3. How many mL of concentrated nitric acid (HNO3, 16.0 M) should be diluted with water in order to make 2.00 L of 2.00 M solution?
32.0 mL
62.5 mL
125 mL
250. mL
500. mL

2007-10-01 16:12:15 · 1 answers · asked by Anonymous in Chemistry